JPS61205845U

JPS61205845U -

Info

Publication number: JPS61205845U
Application number: JP1985090723U
Authority: JP
Priority date: 1985-06-14
Filing date: 1985-06-14
Publication date: 1986-12-25

Description

[Brief explanation of drawings]

第１図はこの考案による車輌盗難警報装置のブ
ロツク図、第２図は同装置の１実施例の回路図、
第３図乃至第５図はこの実施例の常閉スイツチの
開閉状態に応じてこの実施例に用いた抵抗器の接
続が変化する状態を示す図である。１０……常開スイツチ、１２……車輌用電気回
路、１４……警報器駆動回路、１６……常閉スイ
ツチ、１８……警報器。 Fig. 1 is a block diagram of a vehicle theft alarm system according to this invention, Fig. 2 is a circuit diagram of an embodiment of the same device,
3 to 5 are diagrams showing how the connection of the resistor used in this embodiment changes depending on the open/closed state of the normally closed switch of this embodiment. 10... Normally open switch, 12... Vehicle electric circuit, 14... Alarm drive circuit, 16... Normally closed switch, 18... Alarm.

Claims

[Scope of Claim for Utility Model Registration] (1) A normally open switch that is closed when the vehicle's engine key is turned on, a vehicle electrical circuit connected in series to this normally open switch, and parallel to the normally open switch. an alarm drive circuit that operates when the attached normally closed switch is opened, and an alarm connected to the output side of this alarm drive circuit, and the normally closed switch is connected to the engine key. Using the conductive metal part around the key insertion part as one contact,
A vehicle theft alarm system characterized in that the other contact point is a conductive metal part detachably provided on the engine key insertion part. (2) The alarm drive circuit connects the first resistor and the normally closed switch between the input terminal of the oscillation circuit that operates when a voltage higher than the threshold value is supplied to the input terminal and the reference potential point. The output side of the AND circuit is connected to the input terminal via a second resistor, and the first input side of the AND circuit is connected to the input terminal. 1 input side is connected to the high potential side contact of the above-mentioned normally open switch via third and fourth resistors, and the high potential side contact of the above normally open switch is connected to the second input side of the above AND circuit. , the voltage applied to the first input side of the AND circuit is made smaller than the threshold value of the AND circuit when the normally closed switch is closed, and the normally closed switch is opened. The values of the first to fourth resistors are selected such that the values of the first to fourth resistors are greater than the threshold value even when the normally closed switch is closed after being opened, and the connection of the third and fourth resistors is The vehicle theft alarm system according to claim 1, characterized in that the operation of the AND circuit is delayed by a capacitor connected between the point and the low potential side of the normally open switch. .